Spatial cluster analysis for bovine paratuberculosis in Paraiba State, Northeastern Brazil / Análise de aglomerados espaciais para paratuberculose bovina no Estado da Paraíba, Nordeste do Brasil

The aim of this survey was to identify spatial clustering of bovine paratuberculosis positive herds in the State of Paraíba, Northeastern Brazil. The state was divided into three sampling groups: sampling stratum 1 (mesoregion of Sertão), sampling stratum 2 (mesoregion of Borborema), and sampling stratum 3 (mesoregions of Zona da Mata and Agreste). Ten animals were sampled in herds with up to 99 cows aged over 24 months; 15 animals were sampled in herds with 100 or more cows aged over 24 months; and all animals were sampled in those with up to 10 cows aged over 24 months. In total, 2504 cows aged ≥ 24 months were sampled from 480 herds. Indirect enzyme-linked immunosorbant assay (ELISA) test kits were used for Mycobacterium avium subsp. paratuberculosis (MAP) antibody detection. A herd was deemed positive for paratuberculosis if it included at least one positive animal in herds of up to 24 females, and two positive animals in herds with more than 24 females. Spatial clustering was assessed using the Cuzick-Edwards' k-nearest neighbor method and spatial scan statistics. Two significant clustering of positive herds were detected in Northern part of Borborema mesoregion, a border region with the State of Rio Grande do Norte, in which there is a large animal movement from different locations without knowing the sanitary condition of animals. As serological tests for MAP diagnosis are not widely available and are very expensive, as well as replacement or maintenance of livestock by animal purchasing is common in the region, it is concluded that prevention measures should be applied at herd level.(AU)

O objetivo deste estudo foi identificar agrupamentos espaciais de rebanhos positivos para paratuberculose bovina no Estado da Paraíba, Nordeste do Brasil. O estado foi dividido em três grupos amostrais: estrato amostral 1 (mesorregião do Sertão), estrato amostral 2 (mesorregião da Borborema), e estrato amostral 3 (mesorregiões da Zona da Mata e Agreste). Dez animais foram amostrados em rebanhos com até 99 vacas com idade maior ou igual a 24 meses; 15 animais foram amostrados em rebanhos com 100 ou mais vacas com idade maior ou igual a 24 meses; e todos os animais foram amostrados naqueles rebanhos com até 10 vacas. No total, foram amostradas 2504 vacas com idade ≥24 meses de 480 rebanhos. Para a detecção de anticorpos anti-Mycobacterium avium subsp. paratuberculosis (MAP) foram utilizados kits do teste imunoenzimático indireto (ELISA). Um rebanho foi considerado positivo para paratuberculose se apresentasse pelo menos um animal positivo em rebanhos de até 24 fêmeas, e dois animais positivos em rebanhos com mais de 24 fêmeas. Os agrupamentos espaciais foram avaliados com o uso da metodologia k-vizinhos mais próximos de Cuzick-Edwards e estatística espacial de varredura. Dois agrupamentos significativos de rebanhos positivos foram detectados na parte norte da mesorregião da Borborema, uma região de fronteira com o Estado do Rio Grande do Norte onde há intenso movimento de animais de diferentes locais sem o conhecimento do estado sanitário desses animais. Tendo em vista que os testes sorológicos para diagnóstico de MAP não são amplamente disponíveis e muito caros, bem como é comum na região a reposição e manutenção dos rebanhos por compra de animais, conclui-se que medidas de prevenção devem ser aplicadas em nível de rebanho.(AU)

Evaluation of goat based ‘Indigenous vaccine’ against Bovine Johne’s Disease in endemically infected native cattle herds.

‘Indigenous vaccine’ prepared from ‘Indian Bison Type’ a native bio-type of Mycobacterium avium subspecies paratuberculosis strain ‘S5’ of goat origin (goat based) was evaluated in indigenous cattle herds located in gaushalas (cow shelters), endemic for Bovine Johne’s disease. Cows (893) were randomly divided into vaccinated (702 = 626 adults + 76 calves) and control (191 = 173 adults + 18 calves) groups. Response to vaccination was evaluated on the basis of health (mortality, morbidity), productivity (growth rate, reproductive performance, total milk yield), immunological parameters (LTT, ELISA titer), survivability of animals naturally infected with MAP, bacterimia (by specific blood PCR), sero-conversion (by indigenous ELISA) and status of shedding of MAP in feces (by microscopy) in the two groups before and after vaccination. Reduction in MAP shedding [to the extent of 100% in Herd A; and from 82.1% (0 DPV) to 10.7% (270 DPV) in Herd C] was the major finding in vaccinated cows. Whereas, the control group cows have shown no improvement. As the first indicator of vaccine efficacy, MAP bacilli disappeared from the blood circulation as early as 15 days post vaccination, however, peak titers were achieved around 90 DPV. Peak titers initially declined slightly but were maintained later throughout the study period. Control animals did not show any pattern in antibody titers. Mortality was low in vaccinated as compared to the control groups. Vaccination of endemically infected native cattle herds with inactivated whole-cell bacterin of novel ‘Indian Bison Type’ bio-type of goat origin strain ‘S5’ effectively restored health and productivity and reduced clinical BJD. Application of goat based ‘indigenous vaccine’ for therapeutic management of BJD in native cattle herds (gaushalas) is the first of its kind.

Paratuberculose em ruminantes no Brasil / Paratuberculosis in ruminants in Brasil: a review

A paratuberculose ou doença de Johne é uma enterite granulomatosa causada por Mycobacterium avium subsp. paratuberculosis (Map) e comumente afeta ruminantes domésticos, no entanto, pode infectar várias espécies de mamíferos. Está presente nos cinco continentes e é considerada endêmica em algumas regiões pela Organização Internacional de Epizootias (OIE). Pertence à lista de enfermidades notificáveis, que compreende as doenças transmissíveis de importância sócio-econômica e/ou em saúde-pública, cujo controle é necessário para o comércio internacional de animais e alimentos de origem animal. A importância da doença de Johne não se restringe somente aos prejuízos econômicos causados à indústria animal, mas também na possível participação do Map na íleocolite granulomatosa que afeta seres humanos, conhecida como doença de Crohn. No Brasil, a paratuberculose já foi descrita em diversas espécies de ruminantes e em vários estados. Embora os relatos naturais da enfermidade sejam pontuais, acredita-se na possibilidade da transmissão interespecífica e na disseminação do agente através da compra e venda de animais infectados. O objetivo deste artigo foi reunir as informações disponíveis referentes aos aspectos epidemiológicos, clínico-patológicos e laboratoriais da paratuberculose em bovinos, bubalinos, caprinos e ovinos no Brasil, e salientar a necessidade de implementação de medidas de controle sanitário da enfermidade no país, o que possibilitaria a melhoria da qualidade e valorização dos produtos de origem animal no mercado internacional.

Paratuberculosis also known as Johne's disease, is a granulomatous enteritis caused by Mycobacterium avium subsp. paratuberculosis (MAP), an acid-fast bacillus that preferentially resides within host intestinal macrophages. The condition is most commonly seen in domestic ruminants, however MAP can also infect other mammalian species. Paratuberculosis shows a global distribution and is considered endemic in some regions. The World Organization for Animal Health (OIE, Office International des Epizooties), have classified paratuberculosis as a notificable disease; considered to be of socio-economic and/or public-health importance, the control of which is necessary for the international trade of animal and animal products. The importance of paratuberculosis is related primarily to economic losses in the animal industry and also because of a potential role for this bacterium in the pathogenesis of Crohn´s disease, a debilitating condition affecting the digestive tract of humans. In Brazil, paratuberculosis has been reported in a variety of ruminant species and shows a broad geographic distribution. The reported incidence of natural cases in Brazil has been limited, but it is believed that interespecific transmission of MAP and dissemination of the agent is driven by the commercialization of infected animals. The main objective of this paper was to collate the published epidemiological, clinic-pathological and diagnostic information in relation to paratuberculosis in cattle, buffaloes, goats and sheep in Brazil. Moreover, it served as a platform to emphasize the requirement to implement sanitary policies for control of MAP in the county, which may serve to improve the quality and value of animal products on international markets.

Effect of lipoarabinomannan from Mycobacterium avium subsp avium in Freund’s incomplete adjuvant on the immune response of cattle

The aim of the present study was to determine whether lipoarabinomannan (LAM), in combination with Freund’s incomplete adjuvant (FIA), was able to improve cell-mediated and antibody-mediated immune responses against ovalbumin (OVA) in cattle. Twenty-three calves were assigned to four treatment groups, which were subcutaneously immunized with either OVA plus FIA, OVA plus FIA and LAM from Mycobacterium avium subsp avium, FIA plus LAM, or FIA alone. Lymphoproliferation, IFN-γ production and cell subpopulations on peripheral blood mononuclear cells before and 15 days after treatment were evaluated. Delayed hypersensitivity was evaluated on day 57. Specific humoral immune response was measured by ELISA. Inoculation with LAM induced higher levels of lymphoproliferation and IFN-γ production in response to ConA and OVA (P < 0.05). Specific antibody titers were similar in both OVA-immunized groups. Interestingly, our results showed that the use of LAM in vaccine preparations improved specific cell immune response evaluated by lymphoproliferation and IFN-γ production by at least 50 and 25 percent, respectively, in cattle without interfering with tuberculosis and paratuberculosis diagnosis.

Aspectos clínico-patológicos e controle da paratuberculose em rebanho bovino leiteiro / Clinic-pathological aspects and control of paratuberculosis in a dairy cattle herd

A paratuberculose ou doença de Johne é uma enterite granulomatosa causada por Mycobacterium avium subsp. paratuberculosis. Descrevem-se os aspectos epidemiológicos, clínico-patológicos e laboratoriais da paratuberculose em rebanho bovino leiteiro no município de Rio Claro, região Sul do Estado do Rio de Janeiro. No período de 2006 a 2009, oito vacas adultas da raça Girolanda apresentaram diarreia crônico-intermitente e perda progressiva de peso. À necropsia, observaram-se linfonodos mesentéricos aumentados de volume e úmidos ao corte, vasos linfáticos subserosos das alças intestinais proeminentes, serosa do intestino com aspecto anelado e cerebroide e a mucosa espessada, pregueada e com aspecto microgranular. À microscopia havia, desde o duodeno até o reto, inflamação granulomatosa difusa, marcada dilatação dos vasos linfáticos no ápice das vilosidades, linfangiectasia e linfangite granulomatosa na submucosa, muscular e serosa. A inflamação granulomatosa também foi vista nos linfonodos mesentéricos. A coloração de Ziehl-Neelsen revelou variável quantidade de bacilos álcool-ácido resistentes no interior de macrófagos, de células gigantes de Langhans e livres na mucosa e submucosa dos intestinos delgado e grosso e em linfonodos mesentéricos. Em alguns animais, a lâmina própria da mucosa, principalmente do jejuno e íleo exibia acentuada hipertrofia. Mycobacterium avium subsp. paratuberculosis foi isolado em cultivo bacteriano de Herrold com micobactina, a partir de amostras de fezes, de raspado de mucosa intestinal e de leite e identificado pela técnica de PCR IS900. Através da avaliação sorológica semestral, foram analisadas 298 vacas do mesmo rebanho a partir de três anos de idade, observou-se cerca de 40 por cento de animais reagentes ao teste ELISA indireto no período estudado. O diagnóstico da paratuberculose foi baseado nos dados clínico-patológicos, na sorologia, no isolamento e identificação do agente através de cultivo bacteriano e PCR IS900. Após implementação de medidas de controle, tais como eliminação de animais doentes, abate seletivo dos animais soropositivos, separação dos bezerros ao nascer e utilização de banco de colostro, observou-se, nos três anos de estudo, diminuição da ocorrência de casos clínicos no rebanho, de seis casos por ano para cerca de um caso por ano.

Paratuberculosis (Johne's disease) is a granulomatous enteritis of ruminants caused by Mycobacterium avium subsp. paratuberculosis. Epidemiology, clinic-pathological and laboratorial aspects of paratuberculosis in a dairy cattle herd are described. The disease was diagnosed from 2006 to 2009 in eight cows that presented chronic-intermittent diarrhea and chronic weight loss, in the Rio Claro municipality, Rio de Janeiro. At necropsy, the subserosal lymphatic vessels were proeminent and dilated, mesenteric nodes were enlarged and intestinal mucosa was corrugated, thickened and of microgranular aspect. From duodenum to the rectum, histopathology revealed severe and diffuse granulomatous inflammation of the lamina propria and submucosa, broadened and distorted villi, dilatation of the lymphatic vessels in their apex, lymphangioectasia and granulomatous lymphangitis in the submucosa. Ziehl-Neelsen stain showed variable amounts of acid-fast bacilli in macrophages, in Langhans giant cells and freely in the mucosa and submucosa of the small intestine, colon and lymphnodes. In some cows, the lamina propria presented severe hypertrophy, mainly in the jejunum and ileum. Mycobacterium avium subsp. paratuberculosis was isolated through bacterial cultivation of samples taken from feces, intestinal mucosa and milk, and identified through IS900 PCR. From 298 cows older than three years, the percentage of reactive animals was 40 percent by indirect ELISA test. The diagnosis of paratuberculosis was based on clinic-epidemiological data, serology, bacterial isolation in Herrold egg yolk medium with micobactin and on IS900 PCR. After the adoption of control measures, as slaughter of cows with clinical signs, selective slaughter of seropositive cows, removal of the calf from the dam at birth, and use of the colostrum bank, we observed a reduction from six clinical cases to only one case per year, in the last three years of the study.